I tend to concur with Web436, that Berkshire is neither Cheap nor expensive right now. Short term (1-year) maybe it's unlikely to move much higher - based on Jim's analysis of how it has traded since 2008.

But I think some introspection is due because you're looking to get in (back in!) at the highest Berkshire prices ever. Why now, and why did you sell out before? Also what are you invested in now? The answer to those questions can help to formulate a proper plan.

Is there a danger you'll jump back to your old investment when it moves up in price and Berkshire moves down in price? And is your current investment a reasonable earnings-generating investment? If so, maybe stay put.

There are investments I consider more of a collector item, like beanie babies, baseball cards, or bored ape tokens. Out of those I'd move everything out at once.